Cable clamp



Sept. 23, 1930. M. MJCLAYTON CABLE CLAMP Filed June 14, 1929 I gvwenfoy mg 7 2 amen W134 A) Patented Sept. 23, 1930 UNITED STATES PATENT; OFFICE MARTIN M. CLAYTON OF BADEN, PENNSYLVANIA, ASSIGNOR'TO NATIONAL ELECTRIC PRODUCTS CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE CABLE CLAMP Application filed June 14,

This invention relates to cable clamps or connectors of the so-called squeeze type. Clamps of this typeas heretofore constructed have comprised a barrel portion and have included also a cable gripping portion. In some instances the cable gripping portion has been made integrally with the barrel portion, it being partially separated from the barrel by cross-sectional out or slot. In other instances, separate clamping elements have been used 'wherein multiple screwswere employed to draw up the clampin element against the cable. Other clamps have used a single screw and in lieu of using second screws, have employed a pin and slot type of hinged connection intermediate the clamping part or element and cooperating cable supporting member. While certain of the latter devices have obviated the use of multiple screws in all of these forms of clamp, there has been bending of the metal at abrupt angles which is detracted from the. proper gripping action of the clamp upon the cable. This has been true even with certain forms of hinged connections of the pin and slot type. on account of the conformation of the hinge. Accordingl with previous devices, it has not heretofore been possible to provide for free radial action for the clamping means and it also has not been possible to provide a clamping element of such sort that it is enabled to readily conform to a considerable range of cable sizes.

Accordingly, the present invention has for one of its objects the provision of a clamp of such character that the above undesirable action of previous clamps may be obviated.

More particularly, the present inventionhas for its object the provision of a construction which is particularly adapted to permit free radial and other shifting of the clamping element to the general end that eliicient clamping action may be secured without the necessity of abruptly bending the metal of the clamping element.

Another object of the present invention resides in the provision of a clamping element and cooperating and supporting parts therefor so arranged and related that the clamp- 1929. Serial No. 370,925.

ing element is freely flexible for shifting movement in every direction.

A further object of the present invention resides in the provision of a clamping as sembly or connector having one portion provided with a slot affording a hinge and havlng theother cooperating part or clamping element provided with a curved tongue which s so related to the material of the clamp ltself and to the slot that the curved portion of the tongue may freely rock..upon the edge of the slot as well as shift in and out relative to such slot. In this way a floating fulcrum point is afforded and free bodily float of the clamping element is secured while bending of metal parts is minimized if not entirely obviated.

Other objects of the present invention will be hereinafter set forth in the accompanying specliication and claims and shown in the drawlngs, which by way of illustration show what I now consider. to be a preferred, embodiment of the invention.

In the drawings:

Figure l-is a plan view of the complete assembly showing the improved connector used to connect a flexible conduit or cable to the wall of a junction box;

Flg. 2 is a cross-sectional view taken substantially on line 22 of- Fig. 1; I

Flg. 3 is a View similar to Fig. 2 but with the clamping element removed;

Fig. 4 1s a perspective View ofthe clamplng element;

Fig. is a View of the body portion or barrel portlon of the connector in plan view; and

- Fig. 6 shows the tilting action of the'clamp when the cable is attempted to be pulled from the connector.

The body portion of the connector comprises the annular portion lfl'having extend-- ing therefrom a threaded nipple portion 11 ada ted to extend through an opening 12 in t e wall 13 of thejunction box and to be secured in position by a nut 14. Inwardly beyond 10 the connector is provided with a segmental portion 15 which interiorly approximates a semi-circle in contour and which s also provided with a tangentially extendmg portion 16 (see Fig. 2). This tangential portion 16 is provided with a slot 17 disposed as shown in Figs. 2 and 5. On the end opposite from the tangential extension 16, there is a lateral lug or ear 18 which is apertured to receive a screw 19. The clamping element generally designated 20, also has a portion which is substantially circular in contour and one end is provided with a lug-like extension 21 which is apertured and threaded to receive screw 19.

Theend of the clamping element 20 opposite 21, is provided with an extension or tongue portion 22. Such tongue portion extends first outwardly in substantial. alignment with the curve of the portion 20 and thereafter it is bent with a reverse curve as indicated at 23. Adjacent each side of the tongue portion 22 there are two shoulder portions 24. The tongue portion 22 fits loosely in the slot 17. Considerable clearance is provided at the sides of the tongue as shown in Fig. 1 and also considerable clearance is provided above and below thetongue as shown in Fig. 2.

Accordingly, when the cable or flexible conduit, generally designated 25, is placed in position and engaged by tightening up screw 18, the curve 23 provides a curved fulcrum point for the member 20 and prevents its bending irrespective of the position which it assumes. Part 20 can also freely bodily shift relative to part 15 and in this way it can readily accommodate itself to cables of various sizes and when tightening is efi'ected there is a true squeezing actionupon the cable and in addition bending of the clamp on abrupt bends at any point is obviated.

In Fig. 2 the solid lines show the normal position of the clamp. The dotted lines show the clamp open beyond the normal position and in this position the tongue is pulled further out of the slot. The dot and dash lines show the clamp in an extreme closed position in which the tongue is pushed further back into the slot.

It will be appreciated that the curved con formation of the tongue and the relation of the slot to it is such that the clamp can readily adapt itself to clamp down upon an inserted cable Without necessitatingcxcess or substantially any bending of the material of the clamping element. This efi'ect is due to the combined radial and slipping action of the tongue of the clamp in the slot.

Fig. 6 illustrates the action of the clamping element when an attempt is made to pull the cable out of the connector. As shown in this figure, the clamping element will rock and thus close the cable receiving end ,toa still greater extent offering greater resistance to the withdrawal of the cable.

\Vhat I claim is:

1. A cable clamp comprising a body portion provided with a threaded nipple extension thereon and also provided with a segtionand to providefor for floating bodily rocking movement therein upon tightening of the clamping clement upon an inserted cable.

2. A cable clamp adapted to clamp variable sized cable to a body portion, said clamp comprising a body portion which is provided with a segmental cable receiving portion having one end thereof provided with an aperture for a screw and having the other end thereof provided with a slot, a cooperating clamping element having a tongue portion which is curved where it passes through the slot in the body portion so as to be adapted to loosely tit and float as well as rock in the slot in the body member when clamping is effected whereby free bodily rocking of the clamp is provided for and whereby bending of the'metal of the clamp'or of the body portion is obviated, said clamping element also having a threaded aperture in its end remote from the tongue and a fastening screw adapted to extend through the aperture in the end of the body portion and to engage the threaded aperture in the end of the clamping element remote from the tongue for tightening upb the clamping element upon an inserted ca 1e.

3. A cable clamp adapted to clamp a cable in place and to provide for variable clamping action with minimized bendin r of metal parts, said clamp comprising a body portion slotted to receive'a clamping element and curved to accommodate a cable, said body portion also being provided with an aperture to receive the shank of the fastening screw, a clamping element having a tongue fitting in the aforesaid slot and having its opposite end apertured and screw threaded to receive a screw which has its shank passed through the aperture in the body portion, said clamping element intermediate the tongue and screw threaded aperturebeing also curved to accommodate a cable, said tongue portion ofthe clamping element extending first outwardl in substantial ali nment with the curve intermediate part of the clamping element and thereafter being bent with a reversed curve where it asses through the slot tothereby loosely fit t e slot in the body pora free bodily rocking action during clamping and to minimize bending such metal parts during such clampmg.

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4. A cable clamp adapted to clamp variable sized cable to a body portion and to facilitate clamping action, sald clamp comprising a body portion which is provided with a segmental cable receiving (portion having one e end 16 thereof exten tangentially with respect to the inside and outside'of the segmental portion and also provided with a slot which extends perpendlcularly across the tangential extension, said bod portion also having an extended lug upon the end thereof which .is opposite the tangential extension,

said lug having an aperture therein for a screw, a cooperative elampin element adapted to be secured to the b y portion, said clamping portion comprising an intermediate curved portion, an extended lug upon one end of the clamping element provided with a threaded aperture to receive a screw, said clam in element havin its opposite end provide with an exten ed tongue portion which is curved with a reverse curve to that of the intermediate ortion so that it may fit through the slot 0% the body portion and freely rock and shift with respect thereto, and a screw threaded in the aperture of the clamp.- ing means and extending through the aperture of the body portion for tightening up the clamping element with respect to the body portion. I 1

In testimony whereof I hereto aflix my signature.

MARTIN M. CLAYTON. 

